Organic Geochemistry Research Laboratory

Enzyme-Linked Immunosorbent Assay (ELISA)

ELISA is used as both as a quantitative tool and as a screening method to reduce sample load for conventional analysis. Because ELISAs can be used to screen large sample sets at realistic costs, they can facilitate large-scale surveys and monitoring programs that would otherwise be unrealistic. ELISA is a method of analysis that relies on specific interactions between antibodies and antigens to measure a variety of substances. Several USGS water-quality surveys have used ELISA for the analysis of the major crop herbicides in the United States (eg. alachlor, atrazine, cyanazine, and metolachlor) metolachlor).

ELISA Methods

ELISA analyses performed by the Organic Geochemistry Research Laboratory are as follows:

• Atrazine (IMA)
• Cyanazine (IMC)
• Cyclodienes (IMD)
• Fluometuron (IMF)
• Methoprene Acid (IMP)
• Metolachlor (IMM)
• Metribuzin (IMT)
• Microcystin (IMN)

Selected ELISA References

1. Aga, D.S., and Thurman, E.M., 1997, Environmental immunoassays--Alternative techniques for soil and water analysis, in Aga, D.S. and Thurman, E.M., eds., Immunochemical technology for environmental applications: American Chemical Society Symposium Series 657, p. 1-20.

2. Aga, D.S., Thurman, E.M., and Pomes, M.L., 1994, Determination of alachlor and its ethane-sulfonic acid metabolite in water by solid-phase extraction and enzyme-linked immunosorbent assay: Analytical Chemistry, v. 66, no. 9, p. 1495-1499.

3. Aga, D.S., and Thurman, E.M., 1993, Coupling solid-phase (SPE) and enzyme-linked immunosorbent assay (ELISA) for untratrace analysis of herbicides in pristine water: Analytical Chemistry, v. 65, p. 2894-2898.

4. Bastian, K.C., Thurman, E.M., and Rebich, R.A., 1998, Comparison of enzyme-linked immunoassay with gas chromatography/mass spectrometry for analysis of the cotton herbicide fluometuron: Proceedings of the 28th Mississippi Water Resources Conference, April 7-8, 1998, p. 45-55.

5. Dombrowski, T.R., Thurman, E.M., and Mohrman, G.B., 1996, A first application of enzyme-linked immunosorbent assay for screening cyclodiene insecticides in ground water, in VanEmon, J.M., Gerlach, C.L., and Johnson, J.C., eds, Environmental immunochemical methods--Oersoectuves and applications: American Chemical Society Symposium Series 646, p. 170-182.

6. Fallon, J.D., and Thurman, E.M., 1993, Determining the age, transport, and three-dimensional distribution of atrazine in a reservoir by immunoassay, in Morganwalp, D.W., and Aronson, D.A., compilers, U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the technical meeting, Colorado Springs, Colorado, September 20-24, 1993: U.S. Geological Survey Water-Resources Investigations Report 94-4015, v. 1, p. 499-504.

7. Pomes, M.L., Thurman, E.M., Aga, D.S., and Goolsby, D.A., 1998, Evaluation of microtiter-plate enzyme-linked immunosorbent assay for the analysis of triazine and chloroacetanilide herbicides in rainfall: Environmental Science and Technology, v. 32, p. 163-168.

8. Thurman, E.M. and Aga, D.S., 2001, Detection of Pesticides and Pesticide Metabolites Using the Cross Reactivity in Immunoassays, Journal of AOAC International, v. 84, No. 1, p. 163-167.

9. Thurman, E.M., Meyer, M.T., Pomes, M.L., Perry, C.A., and Schwab, A.P., 1990, Enzyme-linked immunosorbent assay compared with gas chromatography/mass spectrometry for the determination of triazine herbicides in water: Analytical Chemistry, v. 62, p. 2043-2048.